Field of the Invention
The invention relates to a photosensitive resin composition, a protective film, and an element having protective film. More particularly, the invention relates to a photosensitive resin composition capable of forming a protective film having good transparency and chemical resistance, a protective film formed by the photosensitive resin composition, and a liquid crystal display element containing the protective film.
Description of Related Art
In recent years, in the field of the semiconductor industry, liquid crystal displays (LCDs) and organic electro-luminescence displays (OELDs), with the size reduction, the demand of the miniaturization of the pattern(s) in the photolithography process is increased. Generally, the finer pattern is formed by exposing and developing a positive photosensitive material having high resolution and high sensitivity; wherein, a positive photosensitive material using a polysiloxane polymer as a component has become the mainstream used in the industry.
Japanese Laid-Open No. 2008-107529 discloses a photosensitive resin composition which can form a cured film of a high degree of transparency. A polysiloxane polymer containing an oxetanyl group or an oxydicarbonyl group is used in the composition. A hydrophilic structure is formed during copolymerization by a ring opening reaction. Although the photosensitive resin composition has a high solubility in the dilute alkaline developer, the chemical resistance of such photosensitive resin composition is poor, and is not acceptable by the industry.
Therefore, it is desirable for the industry to seek a photosensitive resin composition to provide both good transparency and chemical resistance.